Nazi dictator Adolf Hitler greets supporters at a May Day gathering in the Olympic Stadium, Berlin. (Photo by Keystone). 1st May 1938

Members of the federal police carry a Nazi statue at the Interpol headquarters in Buenos Aires, Argentina, Friday, June 16, 2017. In a hidden room in a house near Argentina's capital, police discovered on June 8th the biggest collection of Nazi artifacts in the country's history. Authorities say they suspect they are originals that belonged to high-ranking Nazis in Germany during World War II. (Photo by Natacha Pisarenko/AP Photo)

George Lincoln Rockwell (US Nazi Party, 1966). “George Lincoln Rockwell (March 9, 1918 – August 25, 1967) was the founder of the American Nazi Party. Rockwell was a major figure in the neo-Nazi movement in the United States, and his beliefs and writings have continued to be influential among white nationalists and neo-Nazis”.

A protester dressed as a clown holds an umbrella over a Swiss police officer on a motorbike during a May Day demonstration in Zurich, Switzerland on May 1, 2017. (Photo by Arnd Wiegmann/Reuters)

A reveller walks through the streets in the early hours during traditional May Day celebrations in Oxford, Britain, May 1, 2015. (Photo by Dylan Martinez/Reuters)

Students from the University of St Andrews jump into The North Sea, as a good luck tradition before exams start on the East Sands in St Andrews, Fife, Scotland on May 1, 2018. (Photo by Derek Allan/Alamy Live News)

A ballet dancer attends a photo shooting as activists from the environmentalist group Greenpeace unfurl a giant banner on the Eiffel Tower which reads “Liberty, Equality, Fraternity” in a call on French citizens to vote against the National Front (FN) presidential candidate Marine Le Pen, in Paris, France May 5, 2017. (Photo by Gonzalo Fuentes/Reuters)

A Femen activist is led away by French police in Henin-beaumont, northern France, Sunday, May 7, 2017. Voters across France are choosing a new president in an unusually tense and important election that could decide Europe's future, making a stark choice between pro-business progressive candidate Emmanuel Macron and far-right populist Marine Le Pen. (Photo by Francois Mori/AP Photo)